Fig. 8
X-ray interferometry images of dumbbells with three different size voids and Cantor dust fractals of order = 1 and 2. The transmission images can detect the largest ellipsoids with a major radius of 400 \(\upmu\)m, but not the smaller ellipsoids. The scattering and differential phase contrast images clearly show the 300 \(\upmu\)m and 400 \(\upmu\)m ellipsoids and show faint indications of the 200 \(\upmu\)m ellipsoids. An important parameter for the X-ray scattering image is the sample position within the interferometer. The sample position determines both the X-ray magnification and the interferometer autocorrelation length. The magnification was 2.22 giving an effective pixel size of 33.7 \(\upmu\)m. The sample position between G1 and G2 with a sample-to-detector distance of 50 cm gives an interferometer autocorrelation length of \(\xi\) = 2.6 \(\upmu\)m28, well suited for observing loose powder inside the Cantor dust fractal ellipsoids.
